Treatment of textiles with fluorinated polyethers

ABSTRACT

A polymer adapted for the Shrink resist treatment of textile materials imparting water, stain and/or oil repellency. The polymer includes a fluorinated polyether.

This application is a U.S. national filing under 35 U.S.C. 371 andclaims priority from PCT/GB02/003279, filed Jul. 17, 2002, and fromBritish Application No. 0117336.8 filed Jul. 17, 2001.

This invention relates to polymer treatments for textiles.

Fluorinated polymers may be applied to textile articles so as to renderthem water, oil and/or stain repellent.

There are many processes for imparting a chemical finish to woolgarments to prevent them felting during domestic laundering. The DylonGRB and SIMPLX process are two examples, which apply polymers to thegarments. The polymers may additionally result in other desirableproperties, for example, reduction in pilling.

Woollen garments can be given a shrink resist (felting resist) treatmenteg. by either of the processes named above, and then treated with afluorinated polymer to impart water, stain and/or oil repellency.However, the latter treatment generally results in a harsh handle, andin order to be effective, the polymer must be cured by baking thetreated articles, after drying, at temperatures up to 130° C., which hasa deleterious effect on wool fibre.

The present invention provides a novel polymer for the treatment oftextile materials that does not suffer this disadvantage, and which,surprisingly, has wide application in imparting water, stain and oilrepellency.

The invention comprises a polymer adapted for the treatment of textilematerials, comprising a fluorinated polyether.

The polymer may be of the type -A-B-A-B-, where A is a polyether amineand B is a fluorine compound. B may be a polyether chain, and may be aperfluoro polyether. The perfluoro polyether may be reacted with ahydropolyether.

The polymer may comprise an ester of a perfluoro polyether reacted witha polyether amine, such as polytetrahydrofuran-diamine.

The polymer may have added epichlorohydrin.

The polymer may be adapted for the shrink resist treatment of keratinousfibre and also imparting water, stain and/or oil repellency.

The invention also comprises a polymer comprising a fluorinatedpolyether adapted for the treatment of vegetable and synthetic fibreimparting water, stain and/or oil repellency thereto with a soft handleas compared to fluorinated polyurethanes or fluorinated polyacrylates.

The polymer may be adapted for the treatment of textiles by being inaqueous solution; the concentration of the polymer in the solution maybe up to 20%, for example, 10%.

The invention also comprises a method for making a polymer comprising afluorinated polyether, comprising reacting a polyether amine, such aspolytetrahydrofuran-diamine with an ester of a perfluoroether. The estermay be Fomblin 5027X or Fomblin 5028X, of molecular weightsapproximately 1000 and 1500 respectively, supplied by Ausimont Spa.

The ratio of diamine to ester may be between 7:6 and 2:1, and may be7:6, 5:4, 3:2 or 2:1.

The reaction may be carried out by heating under vacuum in the presenceof an acid, which may be para-toluene sulphonic acid, which may bepresent at 2% by weight in the total reactants.

The reaction may be carried out at between 130° C. and 160° C., say 150°C., the heating being continued for one to three hours, for example twohours. After the heating, the product may be maintained under vacuum fora further period of one to four hours, say three hours. The product maythen be cooled to below 110° C. and, whilst still fluid, dissolved iniso-propanol and water with vigorous stirring. Epichlorohydrin may beadded to this solution and reacted at 65° C. until the pH falls to avalue below 7.2.

Formic acid may then be added to halt the reaction, to give a pH of 3.5The solution may then be diluted with water so as to contain up to 20%,eg. 10% solids.

The invention also comprises a method for the treatment of keratinousfibre comprising applying to it a polymer comprising a fluorinatedpolyether, especially one made by a method as above described.

The polymer may be applied by padding or by coating.

The polymer may be applied by exhausting it on to the fibre.

The polymer may be applied in a treatment bath with liquor to goodsratio of 30:1. The treatment bath may be heated to 40° C.

The polymer may be applied at 4 to 8% by weight on weight of goods.After the treatment, the fibres may be dried at a temperature which needbe no higher than 80° C., (ie. in a tumble drier) even at roomtemperature, thus avoiding deterioration of the fibre and hard handle.

A keratinous fibre may be pre-treated with permonosulphate or chlorineor a chlorine donor, followed by sulphite neutralisation and rinsing.

The invention also comprises a method for the treatment of vegetableand/or synthetic fibre to impart water, stain and/or oil repellency withsoft handle, comprising treating the fibre with a fluorinated polyetheras above described or made by a method as above described.

The polymer may be applied from a solution containing 60 g/l of polymerin water.

The rate of application of polymer to fibre may be 6% polymer by weightof fabric.

For the treatment, the fibre will usually be in fabric, eg. woven orknitted form, but yam or tow may also be treated.

The preparation of a fluorinated polyether according to the inventionand its use in the treatment of textile materials will now be describedwith reference to the following Examples

EXAMPLE 1

Polytetrahydrofuran-diamine (of approximate molecular weight 1700) andFomblin 5027X or 5028X (the esters of a perfluoropolyether, molecularweights approximately 1000 and 1500 respectively, ex Ausimont, Spa) werereacted at various ratios (see Table 1) by heating at 150° C. under avacuum in the present of para-toluene sulphonic acid (2% by weight onthe total weight of reactants). The mixture was heated to 150° C. over aperiod of two hours under vacuum and maintain at this condition for afurther three hours. The reaction mixture was cooled to below 100° C.and, whilst still hot, the resulting product was dissolved iniso-propanol and water with vigorous stirring.

To this solution was added epichlorohydrin according to Table 1, and thewhole mixture was further reacted at 65° C. until the pH of the solutionfell to below a value of 7.2. To halt the reaction, sufficient formicacid was added to give a pH value of 3.5, and the whole was then dilutedfurther with water to give a resulting solution containing approximately10% solids.

TABLE 1 Fomblin Ratio of A Ratio of F content Product reactant (PTHF) toB PTHF of polymer % Ref used (Fomblin) to ech (%) activity SP1252 5027X2:1 0.83 11.5 10 SP1253 5028X 2:1 0.83 16.2 10 SP1254 5028X 3:2 1.2519.2 10 SP1255 5027X 3:2 1.25 14.5 10 SP1256 5028X 1:1 1.25 25.5Insoluble SP1260 5028X 5:4 2.00 22.6 10 SP1261 5028X 7:6 2.86 23.6 10

EXAMPLE 2

Knitted lambswool fabric swatches (2/17 Nm woollen spun yarn) weretreated by the Dylan SIMPL-X method using permonosulphate. Aftersulphite neutralisation and rinsing, each of the swatches was furthertreated with some of the materials produced in Example 1 by exhaustingthe polymer on to the wool swatch in a treatment bath at 40° C. and aliquor to goods ratio of 30:1. The amount of product applied in eachcase was 4.5% by weight on weight of fabric.

For comparison, further treatments were made with Polymer TM (acommercial shrink resist polymer) only at 4% by weight. Two swatcheswere made of each treatment; one was dried at room temperature, thesecond dried in a tumble dryer (70–75° C.). The prepared fabric swatcheswere tested (Table 2) for oil and water repellency immediately and afterwashing for and five machine wash cycles respectively in a domesticwashing machine (using detergent) on a wool cycle. Good water repellencywas achieved and maintained at these levels, although oil repellency waslow, and was generally lost after washing.

TABLE 2 Drying Initial 1 × HLCC7 5 × HLCC7 Product Temp* Oil Water OilWater Oil Water SP1252 RT 2 5 1 3 0 5 TD 2 5 2 5 0 5 SP1253 RT 2 5 1 3 05 TD 2 5 2 5 0 5 SP1254 RT 2 6 0 5 1 5 TD 3 5 2 5 0 5 SP1255 RT 2 5 0 50 5 TD 2 5 0 5 0 5 Polymer RT 0 1 0 2 0 3 TM TD 0 3 0 3 0 3 *RT = Roomtemperature, TD = Tumble Dryer

EXAMPLE 3

Further swatches were prepared in a similar manner to those in Example2, using the material with the highest level of fluorine—SP1261. In thisexample, 8% by weight of fluorinated product was applied to SIMPL-Xtreated wool swatches. A comparison was made with a swatch treated with4% Polymer TM followed (in a fresh bath) by 3% Foraperle 390 (exAtofina) a commercial fluoroacrylate resin for textile treatments.Following the Polymer TM/Foraperle 390 treatment, the treated swatch wasdried in a tumble dryer, then cured at 130° C. for 4 minutes. All otherswatches were dried in a tumble dryer only.

The swatches prepared in this Example were tested for the following:shrink resistance to the WoolMark Company's Total Easy care standard—refTM254; oil repellency to AATCC Method 118; water repellency; sprayrating to BS3702 and durability of these effects to machine washing on awool cycle in a domestic washing machine (20 wash cycles). The resultsare shown in Table 3.

TABLE 3 Initial Results After 20 wool cycle washes Product TM254 OilWater Spray Oil Water Spray SP1261 +0.2% 2 5 4 0 5 3 TM/F390 +0.3% 3 6 40 3 0

EXAMPLE 4

Further applications of the material used in Example 3 were made atlower addition rates to determine the limit of effectiveness of thematerial as both a shrink resistant polymer and repellent finish. Inthese tests, SP1261 was applied at 8%, 6% and 4% by weight on SIMPL-Xtreated knitted wool swatches in the manner described in Example 2. Theshrink-resist performance, oil and water repellency and spray ratingwere determined, and the durability of these effects to 20 wool cyclewashes evaluated (Table 4). The performance of the product was found tobe unaffected by decreasing application levels down to 4%.

TABLE 4 Initial Results After 20 wool cycle washes % SP1261 TM254 OilWater Spray Oil Water Spray 4% +2.6% 2 5 4 0 5 3 6% +0.15% 2 6 4 0 5 38% 0.9% 2 5 4 0 5 3

EXAMPLE 5

The product used in Example 3 (SP1261) was applied to cotton jerseyfabric (single jersey) and woven polyester fabric by a padding processfrom a solution containing 60 g/l of product in water. The pick-up ofliquor on the fabric after padding was adjusted to 100%, giving anequivalent application rate of 6% product by weight of fabric(equivalent to 0.6% solids). After drying in a tumble dryer (70–80° C.)the fabrics were tested for oil and water repellency and compared withuntreated control fabrics. The following results were obtained (Table5).

TABLE 5 Cotton, Cotton + Polyester, Polyester + untreated SP1261untreated SP1261 Oil repellency 0 0 0 1 Water repellency 0 4 0 4

It will be seen that the fluorinated polyether was effective as a waterand stain repellent, even after multiple laundering cycles. It wasinitially effective as an oil repellent, but this property tended to belost on laundering. Nevertheless, for goods which are not normallylaundered, eg. awnings, tent canvasses and so forth, this can be usefulprotection.

The polymer was very effective on keratinous fibre (lambs' wool) as wellas a shrink-resist finish.

On cotton and woven polyester fabrics, the polymer gives waterrepellency without the imposition of a harsh handle.

Clearly, other fluorinated polyethers will have similar, if notidentical effects. Armed with the present disclosure it will bestraightforward to investigate other preparations and treatmentspecifications to achieve useful results.

In addition, it has been found that when wool textiles and fibres aretreated with a polymer in accordance with the invention, they can bewashed at higher temperatures and/or using more agressive washes thanwould normally be the case. For example, a wool swatch treated with thepolymer may be washed in temperatures up to 60° C.

1. A polymer adapted for the treatment of textile materials, comprisinga fluorinated polyether of the type -A-B-A-B-, where A is a polyetheramine and B is a fluorine compound.
 2. A polymer according to claim 1,where B is a polyether chain.
 3. A polymer according to claim 2, where Bis a perfluoro polyether.
 4. A polymer according to claim 3, in whichthe perfluoro polyether is reacted with a hydropolyether.
 5. A polymeraccording to claim 1, comprising an ester of a perfluoropolyetherreacted with a polyether amine.
 6. A polymer according to claim 5, inwhich the polyether amine comprises polytetrahydrofuran-diamine.
 7. Apolymer according to claim 5, with added epichlorohydrin.
 8. A polymeraccording to claim 1, adapted for the shrink resist treatment ofkeratinous fibre and also imparting water, stain and/or oil repellency.9. A polymer according to claim 1, adapted for the treatment ofvegetable and synthetic fibre, imparting water, stain and/or oilrepellency thereto with a soft handle as compared to fluorinatedpolyurethanes or fluorinated acrylates.
 10. A polymer according to claim1, in aqueous solution.
 11. A polymer according to claim 10, in whichthe concentration of the polymer in the solution is up to 20%.
 12. Apolymer according to claim 11, in which the concentration is 10%.
 13. Amethod for making a polymer according to claim 1, comprising reactingpolytetrahydrofuran-diamine with a ester of a perfluoroether.
 14. Amethod according to claim 13, in which the ester is Fomblin 5027X.
 15. Amethod according to claim 13, in which the ester is Fomblin 5028X.
 16. Amethod according to claim 13, in which the ratio of diamine to ester isbetween 7:6 and 2:1.
 17. A method according to claim 16, in which theratio is 7:6.
 18. A method according to claim 16, in which the ratio is5:4.
 19. A method according to claim 16, in which the ratio is 3:2. 20.A method according to claim 16, in which the ratio is 2:1.
 21. A methodaccording to claim 13, in which the reaction is carried out by heatingunder vacuum in the presence of an acid.
 22. A method according to claim21, in which the acid is para-toluene sulphonic acid.
 23. A methodaccording to claim 22, in which the acid is present at 2% by weight onthe total of reactants.
 24. A method according to claim 21, in which thereaction is carried out at between 130° C. and 160° C.
 25. A methodaccording to claim 24, in which the reaction is carried out at 150° C.26. A method according to claim 21, in which the heating is continuedfor between one and three hours.
 27. A method according to claim 26, inwhich the heating is continued for two hours.
 28. A method according toclaim 26, in which after the heating the product is maintained undervacuum for a further period of one to four hours.
 29. A method accordingto claim 28, in which the further period is three hours.
 30. A methodaccording to claim 28, in which the product is cooled to below 110° C.and, whilst still fluid, dissolved in iso-propanol and water withvigorous stirring.
 31. A method according to claim 30, in whichepichlorohydrin is added to the solution and reacted at 65° C. until thepH falls to a value below 7.2.
 32. A method according to claim 24, inwhich formic acid is added, to halt the reaction, to give a pH of 3.5.33. A method according to claim 32, in which the solution is dilutedwith water so as to contain up to 20% solids.
 34. A method according toclaim 33, in which the solution is diluted with water so as to contain10% solids.
 35. A method for the treatment of keratinous fibrecomprising the step of applying a polymer comprising a fluorinatedpolyether of the type —A-B-A-B- where A is a polyether amine and B is afluorine compound.
 36. A method according to claim 35, in which thepolymer is applied by padding.
 37. A method according to claim 35, inwhich the polymer is applied by coating.
 38. A method according to claim35, in which the polymer is applied by exhausting it on to the fibre.39. A method according to claim 38, in which a treatment bath is heatedto 40° C.
 40. A method according to claim 35, in which the polymer isapplied at 4–8% by weight on weight of goods.
 41. A method according toclaim 35, in which, after the treatment, the fibres are dried at atemperature no higher than 80° C.
 42. A method according to claim 35, inwhich the fibre is a keratinous fibre pre-treated with permonosulphate,chlorine or a chlorine donor, followed by sulphite neutralisation andrinsing.
 43. A method for the treatment of vegetable and/or syntheticfibre to impart water, stain and/or oil repellency with soft handlecomprising treating the fibre with a polymer according to claim
 1. 44. Amethod according to claim 43, in which the polymer is applied from asolution containing 60 g/l of polymer in water.
 45. A method accordingto claim 44, in which the rate of application of polymer to fibre is 6%polymer by weight of fabric.
 46. A method for treating a textile fabricaccording to claim 35.